Imaging sensors, such as those found in still-cameras and video-cameras, have a plurality of photosensitive receptors. Typically, the receptors are a Complementary Metal Oxide Semiconductor (CMOS) device. Photons of light are collected on photosites of the receptors, typically there is one photosite for each pixel. Typically, the photons are directed at the photoreceptors of the imaging sensor via one or more lenses. An electrical charge is produced in the silicon of the receptor for that photosite, where the charge is proportional to the intensity of the light received. The value of each charge is turned into a digital value by an analogue-to-digital converter.
For conventional colour imaging sensors, a quarter of the photosites record red light, another quarter record blue light, and the remaining half record green light. Typically, this filtering of light to each photosite is achieved by placing a coloured filter on each respective photosite, referred to as a Bayer filter array. Each of the colour pixels are interpolated, via a mosaic operation, with colour data in neighbouring photosites to assign a full colour value to each pixel.
Typically, when a conventional aperture is opened, all the photoreceptors receive light at the same time, which means that each pixel contributes approximately equally to the image. In other cases, there may be a rolling shutter, that successively blocks some photons from reaching the imaging sensor; thus, providing temporal scanning across the imaging sensor, either vertically or horizontally. The selectivity of the photosites coming from which set of photosites are collectively being blocked by the shutter at a certain instant.
It is therefore an object of the present invention to provide a method and system in which the conventional disadvantages are obviated or mitigated, and attainment of desirable attributes is facilitated.